Have you read 1984 yet? It’s a work of fiction, but very insightful.

I use a ConnectPRO UD-14+KIT, 4-Port DVI+USB DDM KVM Switch:

https://connectpro.com/products/ud-14-dvi-d-kvm-switch-for-one-monitor-and-four-computers

It supports four machines, but I use it with either 2 or 3. It works well, I have no complaints

It’s possible to have only one earphone working if the connector is not pushed all the way into the jack.

Firefox.

Wow, this is really great. I’ve been printing, signing, then scanning the signed documents with KDE. I’ll be using this method next time. Thanks!